Rails - Apr 2005 - Rails 0.12.0: Eager associations, new Base.find API, assertions revisited, more Ajax!

The time had come to butcher the piggy-back query and introduce real  
association loading through outer joins. Behold, the glorious eager  
loading of associations that makes it silly easy to fetch not 1, 2, but  
unlimited associations alongside any record in a single query. Turning  
50 database queries into 1 never felt this good.

# Turning N+1 queries into 1
for post in Post.find(:all, :include => [ :author, :comments ])
   puts "Post:            " + post.title
   puts "Written by:      " + post.author.name
   puts "Last comment on: " + post.comments.first.created_on
end

Read more:  
http://ar.rubyonrails.com/classes/ActiveRecord/Associations/ 
ClassMethods.html (Scroll down to Eager loading of associations)

And to match the eager loading, we''re introducing a brand new unified  
API for Base.find, which works the same whether you''re searching for a
specific id, the first record, or all the records. By using named  
options we alleviate your poor brain for remembering whether the  
ordering option was argument number 3 or 4.

Person.find(1, :conditions => "administrator = 1", :order =>  
"created_on DESC")
Person.find(1, 5, 6, :conditions => "administrator = 1", :order
=>
"created_on DESC")
Person.find(:first, :order => "created_on DESC", :offset => 5)
Person.find(:all, :conditions => [ "category IN (?)", categories],
:limit => 50)
Person.find(:all, :offset => 10, :limit => 10)

Read more:  
http://ar.rubyonrails.com/classes/ActiveRecord/Base.html#M000226

Better testing
--------------
We''ve also slashed the huge number of assertions for testing  
controllers. In one fell swoop, we''ve gone from around thirty to a shap
seven. The remaining assertions are more flexible than before, not  
nearly as hard to remember, and are followed on by the fantastic new  
assert_tag, which makes examining the HTML output of an action so much  
easier than the XHTML/REXML fumblings of yesterday.

Read more: http://ap.rubyonrails.com/classes/Test/Unit/Assertions.html

More Ajaxing
------------
Of course, we couldn''t make a new release without asserting the  
undisputed position as the number one framework for doing Ajaxed  
applications. This release contains a bunch of new smooth effects  
(http://mir.aculo.us/demos/effects/demo1.html) for visualizing your  
non-refreshing actions. It''s now much easier to make Ajaxed  
applications that treat the unfortunate without Javascript nicely with  
request.xml_http_request? and alternative targets for ajax links and  
forms. We''ve also added periodically_call_remote that can be used to  
Ajax-update a given block every so seconds.

In the next release, which will be not very far off, we''re also adding
awesome support for both Google Suggest-like search boxes and for  
upload progress indicators (http://sean.treadway.info/demo/upload).  
There''s a powerful team behind pushing the envelope on this. We have so
not seen the end of it.

A total of 96 changes, tweaks, and fixes
----------------------------------------
All these goodies are just the tip of the iceberg, though. There''s a  
total of 96 new features, changes, tweaks, and fixes packed into this  
monster of a release. And we didn''t even have time to push in all of  
the pending patches (http://dev.rubyonrails.com/report/3). How''s that  
for an action-packed three weeks since the last release?

Fully backwards compatible!
---------------------------
Despite the true onslaught of new features, fixes, and goodies, we''ve  
managed to keep this release fully backwards compatible with 0.11.1. So  
you just do a "gem update rails" and all the new stuff is available
for
use in your current application (to take advantage of the new JS  
effects you''ll want to copy that one over, though -- use rails . in  
your app dir to get that for free).

See the changelogs for the full story:

* Rails: http://api.rubyonrails.com/files/CHANGELOG.html
* Active Record:  
http://api.rubyonrails.com/files/vendor/rails/activerecord/ 
CHANGELOG.html
* Action Pack:  
http://api.rubyonrails.com/files/vendor/rails/actionpack/CHANGELOG.html
* Action Web Service:  
http://api.rubyonrails.com/files/vendor/rails/aws/CHANGELOG.html
* Action Mailer:  
http://api.rubyonrails.com/files/vendor/rails/actionmailer/ 
CHANGELOG.html
* Active Support:  
http://api.rubyonrails.com/files/vendor/rails/activesupport/ 
CHANGELOG.html
--
David Heinemeier Hansson,
http://www.basecamphq.com/   -- Web-based Project Management
http://www.rubyonrails.org/  -- Web-application framework for Ruby
http://www.loudthinking.com/ -- Broadcasting Brain

On 4/19/05, David Heinemeier Hansson
<david-OiTZALl8rpK0mm7Ywyx6yg@public.gmane.org>
wrote:
> The time had come to butcher the piggy-back query and introduce real
> association loading through outer joins. Behold, the glorious eager
> loading of associations that makes it silly easy to fetch not 1, 2, but
> unlimited associations alongside any record in a single query. Turning
> 50 database queries into 1 never felt this good.
Congratulations to everyone involved in adding this great new feature.
  A seriously cool enhancement.

It''s a fairly major change and there may well be bugs, once
you''ve
integrated eager associations into your applications please file bug
reports for anything you notice.

Another thing to consider is that the sooner you implement this
functionality into your application, the more likely it is that we''ll
fix any problems that you find. ;)

http://dev.rubyonrails.org/

-- 
Cheers

Your friendly Trac dweller.

Congratulations to David and team for another fantastic release giving
more than a few wows, while reading over the changelogs.

I''ve upgraded with the only minor problem, which isn''t really
a bug in
my ActionMailer unit tests, where the new smart utf8 encoding messed
around with my hardcoded expected subject. I fixed my code and it now
works great.

I cant wait to try the new effects and the eager loading of
associations. This was another one that the Hibernate crew was using
against us and is definitely a brilliant improvement.


Regards
Pelle

BRILLIANT!!

Huge thanks to all contributers!

--Steve

Hello,

I encouter problem with flash.now when upgraded to 0.12. It''s not 
working anymore. Althoug normal flash is working. When I set it in 
controller and check it, it''s there but on the begining of the template
(in layout) @flash is empty hash. I somehow feel it could be related to 
new partial rendering or maybe it''s just my own problem so I want to 
ask if somebody solves same problems.

Thans alot. I even look in flash.rb but looks identical like older 
version, so nothing to see here. I will also continue with finding 
reason of this, so if you''ll give me some hints, it will be nice.

Thanks alot.
--
Pepe